The applicant, after completion of medical school training at U. of Miami, and clinical training in medicine at U. of Tennessee, began subspecialty training in gastroenterology at the U. of Florida. During the fellowship, sufficient clinical time was devoted to patient care, consultations, and learning endoscopy, colonoscopy and other related procedures. The applicant studied in the basic laboratories of John Mathias, MD and Charles Sninsky, MD, investigating the enteric nervous system and small bowel motility. Some of those studies involved the effects of microtubule altering agents on intestinal myoelectric activity and generated a need for further study and training in order to more fully investigate the area of cytoskeletal proteins in the enteric nervous system. The environment at the U. of Florida is ideal for such studies by the applicant. Collaboration with and sponsorship of Daniel Purich, PhD, who is chairman of Biochemistry and Molecular Biology, and internationally respected expert in microtubule interactions, has led the applicant to graduate course work in cellular biology and investigations of microtubule polymerization. Gerry Shaw, PhD, the secondary sponsor, respected for his work with neurofilament proteins, helped direct studies using immunolocalization to examine neurofilaments in enteric neurons. The proposed project involves the study of cytoskeletal proteins in enteric neurons. Based on their unique location between muscle layers and constant mechanical stress, we hypothesized that cytoskeletal structural proteins in enteric neurons might be modified. Preliminary studies on neurofilament protein immunoreactivity in enteric neurons suggests that they are different as compared to brain neurons. we propose to 1) continue the immunoreactivity studies of neurofilaments and 2) to study other cytoskeletal proteins within enteric neurons, in both 3) developing as well as adult intestine. 4) We will establish enteric neuron cell cultures to take these studies beyond the confines of the intestinal wall and 5) isolate and purify neurofilament and microtubule proteins from enteric neurons for further structural characterization.